Rothman was founder and global vice president at eBay Motors, which he reportedly grew to a $14 billion annual global business accounting for one-third of eBay’s revenue. He has a broader interest in building marketplaces, as outlined in a guest column for TechCrunch. And that’s all relevant since Apartment List plans to expand beyond apartments into other types of marketplaces, including one for autos, in 2013.

“Simon was instrumental in transforming eBay from a niche U.S.-only collectibles auction site into a major global commerce platform,” said Apartment List co-founder and CEO John Kobs in a press release. “His expertise in building thriving marketplaces is going to be essential as we transition from leading a single category search experience to become a multi-category marketplace that unseats Craigslist.”

The company initially focused on personalized apartment recommendations, but it currently describes itself as the Kayak for apartment listings, “consolidating millions of properties from hundreds of well-known listing services,” with features like listing sharing and neighborhood information. The company says it’s used by 600,000 apartment searchers every month.